It looks like one of the tracebacks isn't being caught but the thing causing the
problem, I think is the file /etc/yum.repos.d/dries.repo
Attach that file and I'll bet I can find out what's wrong with it.

Please change the bug summary to something useful - when searching for other
bugs for yum, prior to posting a bug to check that it hasn't already been
reported seeing a bug with "Yum Problem" as the description is totally unhelpful.